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Cryo-EM structure of TGFBIp fibrils driven by a corneal dystrophy-linked mutation enables design of peptide inhibitors of aggregation.

Corneal dystrophy is a heterogeneous group of diseases which manifests clinically by progressive corneal opacity and diminishing visual acuity. A group of corneal dystrophies are linked to autosomal dominant mutations in transforming growth factor β-induced protein (TGFBIp) and characterized by extracellular amyloid-positive deposits of unknown molecular structure. Here, we determined the cryogenic-electron microscopy (cryo-EM) structure of amyloid fibrils formed by the TGFBIp FAS1-4 domain with corneal dystrophy-linked mutation V624M. The L569 to N609 fibril core, which includes the Y571-R588 segment enriched in patient corneal deposits, forms symmetrical protofilaments with internal solvent channels. Leveraging this structure, we designed peptide inhibitors intended to bind onto fibril ends to block elongation, targeting the unequal growth of symmetrical protofilaments. Our G1 and H4 inhibitors exhibit concentration-dependent reduction of TGFBIp FAS1-4 aggregation as assessed by Thioflavin T, solubility fractionation, and electron microscopy. Our work illustrates how fibril structures can guide rational inhibitor design and suggests the targeting of protein aggregates as a therapeutic approach for corneal and ocular diseases.

betaIG-H3 Protein

Efficacy and Safety of the C3 Inhibitor Pegcetacoplan in Paroxysmal Nocturnal Hemoglobinuria: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the efficacy and safety of the complement C3 inhibitor pegcetacoplan in patients with paroxysmal nocturnal hemoglobinuria (PNH). METHODS: PubMed, Embase, Web of Science, and Cochrane Library were systematically searched for studies reporting pegcetacoplan use in PNH. Outcomes included transfusion-requirement, hemoglobin normalization, mean hemoglobin levels, lactate dehydrogenase normalization, reticulocyte count normalization, and safety endpoints. Pooled proportions with 95% confidence intervals were calculated using random-effects models, and heterogeneity was assessed using the I2 statistic. RESULTS: Five studies comprising 271 patients were included. Transfusion avoidance was observed in 80.6% of patients, with a pooled transfusion-requirement rate of 19.4%. LDH normalization occurred in 68.5% of patients (I2 = 0%). Hemoglobin normalization was observed in 42.9%, while reticulocyte count normalization reached 66%. Any-grade adverse events occurred in 83.5% of patients, most commonly pyrexia, headache, and dizziness. Serious adverse events occurred in 16.6%, decreasing to 12% after sensitivity analysis. Breakthrough hemolysis was reported in 14.8%, and infections in 17%. CONCLUSION: Pegcetacoplan demonstrates consistent efficacy signals across key hematologic endpoints and an acceptable safety profile, supporting its potential role as an important therapeutic option, particularly in patients with persistent extravascular hemolysis despite C5 inhibition.

Humans

Impact of estimated total blood volume on NT-proBNP response to angiotensin receptor-neprilysin inhibition in acute heart failure: Insights from the PREMIER study.

BACKGROUND: Sacubitril/valsartan (Sac/Val) reduces N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in acute heart failure (AHF), particularly in patients with reduced ejection fraction. However, whether estimated total blood volume (TBV), calculated using anthropometric equations, is associated with heterogeneity in biomarker response remains uncertain. METHODS: This post hoc exploratory sub-analysis of the PREMIER randomized trial evaluated whether baseline estimated TBV was associated with heterogeneity in NT-proBNP reduction after Sac/Val compared with angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEI/ARB) therapy. Estimated TBV was calculated using validated anthropometric equations and dichotomized at the median (4.05 L). Patients were further stratified by left ventricular ejection fraction (LVEF <40% vs &#x2265;40%). The primary endpoint was the proportional change in NT-proBNP from baseline to Week 8. RESULTS: Among 376 patients, 372 with baseline estimated TBV data were analyzed. In the high TBV group, Sac/Val was associated with greater NT-proBNP reduction than ACEI/ARB (-56% vs -32%; ratio of change, 0.67; 95% confidence interval, 0.53-0.84; P = .001), whereas no significant difference was observed in the low TBV group (P for heterogeneity = 0.063). In patients with LVEF <40%, Sac/Val was associated with greater NT-proBNP reduction in both TBV groups. In patients with LVEF &#x2265;40%, Sac/Val was associated with greater NT-proBNP reduction in the high TBV group, whereas the point estimate in the low TBV group numerically favored ACEI/ARB. CONCLUSIONS: In this exploratory post hoc analysis, higher estimated TBV was associated with greater NT-proBNP reduction after Sac/Val, particularly among patients with LVEF &#x2265;40%. These findings are hypothesis-generating and require external validation. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05164653; Japan Registry of Clinical Trials, jRCTs021210046.

Humans

Effects of semaglutide and empagliflozin on markers of endothelial function in persons with type 2 diabetes: A post hoc analysis of a randomized clinical trial.

AIMS: The endothelium maintains vascular health by regulating blood flow and protecting against inflammatory damage. In type 2 diabetes (T2DM), however, hyperglycemia, hypertension, and hyperlipidemia place a significant burden on the endothelium, potentially leading to atherosclerosis and cardiovascular disease (CVD). While semaglutide and empagliflozin have been shown to reduce CVD risk in T2DM, it remains unclear whether these benefits are mediated by improved endothelial function. This post-hoc analysis explores the effects of these agents on markers of endothelial function, i.e. the reactive hyperaemic index (RHI) and the endothelial-derived cell adhesion molecules (CAMs) E-Selectin, ICAM-1, P-Selectin, and VCAM-1. METHODS: This was a post-hoc analysis of a 32-week randomized trial evaluating the separate and combined effects of semaglutide and empagliflozin on cardio-renal organ damage. One hundred and twenty participants with type 2 diabetes, age&#xa0;&#x2265;&#xa0;50 were randomized to four groups (semaglutide, empagliflozin, the combination or placebo). An increase in RHI and/or a decrease in CAMs were considered beneficial. RESULTS: RHI increased compared to baseline (0.11, 95%CI [0.008;0.21], p&#xa0;=&#xa0;0.03) but not compared to placebo in the semaglutide group (0.11, 95%CI [-0.04;0.24], p&#xa0;=&#xa0;0.16). There was no effect on RHI in the empagliflozin group. Compared to placebo, E-Selectin decreased significantly in the semaglutide and combination groups (-9, 95%CI [-14.1;-5.1] p&#xa0;<&#xa0;0.01 and&#xa0;-&#xa0;9, 95%CI [-14.3; -5.2] p&#xa0;<&#xa0;0.01, respectively). VCAM-1 increased in the same groups, compared to placebo (12.3, 95%CI[2.8;20.8] p&#xa0;=&#xa0;0.01 and 16.2, 95%CI [7.2;24.3], p&#xa0;<&#xa0;0.01, respectively).P-Selectin and ICAM-1 was not significantly affected in any of the groups, compared to placebo (p&#xa0;&#x2265;&#xa0;0.11 and p&#xa0;&#x2265;&#xa0;0.09, respectively). CONCLUSION: Semaglutide improved endothelial function compared to baseline, but not significantly versus placebo, which likely is due to limited power. CAM responses were heterogeneous, suggesting distinct roles in endothelial dysfunction and atherosclerosis. ClinicalTrialsRegister.eu: EudraCT 2019-000781-38.

Aged

Protein isolation markedly enhances in vitro digestibility, nutritional quality, and bioactivity of fungal mycelial proteins.

Fungal mycelial proteins are promising sustainable protein sources, yet their nutritional utilization is often limited by structural constraints. This study systematically evaluated the effects of protein isolation on the proteomic composition, gastrointestinal digestion behavior, amino acid utilization, and bioactivity of Pleurotus citrinopileatus mycelial proteins. Quantitative proteomics identified 3591 proteins, of which 3374 were shared between mycelial flour (PCMF) and protein isolate (PCMPI), indicating that PCMPI primarily represents the soluble proteome fraction. In vitro digestion revealed that PCMPI exhibited significantly higher digestibility (93.98%) than PCMF (42.98%) (p&#xa0;<&#xa0;0.05), reaching levels comparable to whey protein isolate. Enhanced enzymatic accessibility in PCMPI promoted rapid peptide generation during the gastric phase and efficient amino acid release during the intestinal phase, resulting in higher peptide (634.76&#xa0;mg/g) and free amino acid levels (341.69&#xa0;mg/g) at the digestion endpoint. Consequently, PCMPI achieved a balanced amino acid profile with a PDCAAS of 1.0. Moreover, its digestion products exhibited stronger antioxidant activity (IC&#x2085;&#x2080;&#xa0;=&#xa0;8.36&#xa0;mg/mL) and ACE inhibitory activity (IC&#x2085;&#x2080;&#xa0;=&#xa0;15.65&#xa0;mg/mL) compared with PCMF. Mechanistically, protein isolation disrupted the cell wall matrix, shifting digestion from a structure-limited to an accessibility-driven regime. Collectively, these findings demonstrate that protein isolation markedly enhances the digestibility, nutritional quality, and functional potential of mycelial proteins, supporting their application as high-value sustainable protein ingredients.

Digestion

Insulin, Semaglutide and Dapagliflozin in Adults With Type 1 Diabetes: Design and Methods of Triple Therapy for Type 1 Diabetes (TTT1)-An International Phase 3 Clinical Trial.

AIMS: Attaining target glycaemia can be a challenge in Type 1 Diabetes (T1D) due to insulin-induced weight gain. Adjunct therapy with modern glucose-lowering agents developed for type 2 diabetes (T2D) has great potential but may be insufficiently efficacious and carries risks of hypoglycaemia and ketosis. We designed the first Phase 3 clinical trial to assess the efficacy and safety of adding a Glucagon-Like Peptide 1 receptor agonist (GLP-1RA) and a Sodium-Glucose Co-transporter (SGLT2) Inhibitor to insulin therapy in overweight and obese adults with T1D and glycaemia above target (HbA1c 7.5%-11.0% inclusive) (NCT03899402). MATERIALS AND METHODS: In Period 1, participants are randomized 2:1 (open label) for 26&#x2009;weeks to semaglutide and insulin (uptitrated to 1.0&#x2009;mg weekly) or standard insulin therapy. In Period 2, those randomized to semaglutide and insulin in Period 1 are further randomized (double-blind) for 26&#x2009;weeks to dapagliflozin (10&#x2009;mg daily) or placebo, in addition to semaglutide. The primary objective is to compare change in HbA1c on 'triple therapy' (dapagliflozin, semaglutide and insulin) with 'dual therapy' (placebo, semaglutide and insulin). Secondary objectives include comparisons of triple therapy with standard insulin therapy and dual therapy (semaglutide and insulin) with standard insulin therapy. Safety outcomes include hypoglycaemia and ketosis. A sample size recalculation during the trial based on analysis of masked data revised the original recruitment target from 114 to 82 participants. CONCLUSION: The TTT1 trial will provide clinically useful information on combination adjunct therapy in the treatment of T1D.

Humans

Diabetic macular edema and GLP-1 receptor agonist use: a systematic review and meta-analysis.

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are widely used for type II diabetes and obesity because of their cardiometabolic benefits. However, concerns regarding potential ocular adverse effects, particularly diabetic macular edema (DME), have prompted the need to clarify their retinal safety. METHODS: A systematic review and meta-analysis study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology statements (PROSPERO registration: CRD420251176164). MEDLINE (Ovid), EMBASE (Ovid), CENTRAL (Ovid), Web of Science, and PubMed were searched from inception to October 24, 2025. Randomized trials and observational cohort or case-control studies, including individuals with diabetes without baseline DME and exposed to GLP-1RAs were eligible. Two reviewers independently screened studies, extracted data, and assessed risk of bias using ROBINS-I. Certainty of evidence was evaluated using Grading of Recommendations, Assessment, Development, and Evaluation. Random-effects models were used to pool incidence proportions and hazard ratios (HRs). RESULTS: Thirteen retrospective cohort studies (2021-2025) using large real-world databases were included. Across 6 studies, the pooled proportion of incident DME among GLP-1RA users was 0.14 (95% CI: 0.07-0.23; I&#xb2;&#x202f;=&#x202f;99.8%). Compared with mixed antihyperglycemic therapies, GLP-1RA use was not associated with increased DME risk (pooled HR: 0.81, 95% CI: 0.52-1.26). GLP-1RAs were associated with a higher relative risk of DME compared with sodium-glucose cotransporter-2 inhibitors (HR: 1.50, 95% CI: 1.17-1.94) but not compared with dipeptidyl peptidase-4 inhibitors (HR: 0.90, 95% CI: 0.69-1.19). Evidence certainty was very low. CONCLUSION: Current low-certainty observational evidence does not support an overall increased risk of DME with GLP-1RA use. Prospective studies are needed to clarify comparative retinal safety.

Humans

A novel peptide encoded by circTLL1 drives osimertinib resistance in lung cancer by modulating the NT5C2/Ras/PI3K axis.

BACKGROUND: Acquired resistance to osimertinib, a third-generation EGFR tyrosine kinase inhibitor, remains a major clinical challenge in the treatment of non-small cell lung cancer (NSCLC). Although circular RNAs (circRNAs) have been increasingly implicated in drug resistance, most studies have focused on their canonical role as microRNA sponges, while their capacity to encode functional micropeptides remains largely unexplored. This study aimed to identify novel circRNAs involved in osimertinib resistance and to characterize their regulatory functions at the protein level. METHODS: Osimertinib-resistant (OR) NSCLC cell lines were established and validated. High-throughput RNA sequencing was performed to compare the circRNA expression profiles between parental and OR cells. The function of the candidate circRNA was assessed through a series of in vitro and in vivo experiments, including cell viability assays, apoptosis analysis, and xenograft mouse models. Mechanistic investigations involved mass spectrometry, co-immunoprecipitation and western blotting to explore its protein-coding potential and downstream signaling pathways. RESULTS: We identified a novel circRNA, termed circTLL1, that was stably and significantly upregulated in OR-NSCLC cells. Functionally, overexpression of circTLL1 promoted osimertinib resistance, whereas its knockdown restored drug sensitivity both in vitro and in vivo. Mechanistically, we discovered that circTLL1 harbors an open reading frame (ORF) that is translated into a novel 90-amino-acid protein, which we designated circTLL1-90aa. Further investigation revealed that circTLL1-90aa directly interacts with and promotes the degradation of 5'-nucleotidase, cytosolic II (NT5C2), thereby uncoupling nucleotide metabolism from its normal regulatory constraints. The consequent downregulation of NT5C2 leads to elevated GTP levels and leading to the sustained activation of the downstream Ras/PI3K/AKT signaling pathway. CONCLUSION: Our findings unveil a previously unrecognized circRNA/micropeptide/metabolism cascade underlying osimertinib resistance. The identification of the circTLL1-90aa/NT5C2/Ras/PI3K axis not only expands the functional repertoire of the non-coding genome but also provides new insights into the complexity of drug resistance. Given its selective upregulation in resistant cells, circTLL1-90aa holds promise both as a predictive biomarker for treatment stratification and as an actionable therapeutic target, offering a novel strategy to overcome osimertinib resistance in NSCLC patients.

Pyrimidines

Pegcetacoplan Delivers Real-World Therapeutic Benefits and Reduces Disease Burden for Patients With Paroxysmal Nocturnal Haemoglobinuria: A Systematic Literature Review of Pegcetacoplan Real-World Clinical and Patient-Reported Outcomes.

AIMS: Paroxysmal nocturnal haemoglobinuria (PNH) is an ultra-rare, acquired, non-malignant haematological disorder that, if left untreated, can lead to significant morbidity. This systematic literature review (SLR) summarized real-world evidence (RWE) for pegcetacoplan, a complement 3/3b inhibitor (C3i) available since 2021. METHODS: The SLR (PROSPERO-CRD420251043506) followed 2020 PRISMA guidelines and included RW studies of pegcetacoplan (n&#x2009;>&#x2009;1 pts.; English; to April 2025) in adults (age&#x2009;&#x2265;&#x2009;18&#x2009;years) with PNH. RESULTS: Of 409 identified records, 39 qualified, representing 12 distinct studies. Six studies (n&#x2009;=&#x2009;4-39) reported median haemoglobin (Hb) with baseline 8.1-9.6&#x2009;g/dL. Ending median Hb and maximum pegcetacoplan durations were: 12.0&#x2009;g/dL at 12&#x2009;months, 11.1-12.1&#x2009;g/dL at 6&#x2009;months (3 studies), and 11.1&#x2009;g/dL at 3&#x2009;months (1 study). In 4 other studies (n&#x2009;=&#x2009;48-70), ending mean Hb (maximum pegcetacoplan duration) was: 11.3&#x2009;g/dL (7.2&#x2009;months), 11.5&#x2009;g/dL (6.6&#x2009;months), 11.5&#x2009;g/dL (5.9&#x2009;months), and 11.58&#x2009;g/dL (3&#x2009;months). Six studies reported reduced absolute reticulocyte count (ARC; n&#x2009;=&#x2009;4-39) from baseline median 155-301&#x2009;&#xd7;&#x2009;109/L to median 56-106&#x2009;&#xd7;&#x2009;109/L from 14&#x2009;days of pegcetacoplan, maintained to maximum pegcetacoplan of 1-12&#x2009;months. Three studies reported lactate dehydrogenase (LDH; n&#x2009;=&#x2009;4-62); all showed reductions from baseline median 543.0 to 161.7&#x2009;U/L after 3&#x2009;months, and baseline median 299.5-316.0&#x2009;U/L to 193.5-187.0&#x2009;U/L after 6&#x2009;months of pegcetacoplan. In complement 5 inhibitor-na&#xef;ve, LDH reduced from 977.8 to 358.9&#x2009;U/L after 8.4&#x2009;months, and 503.6 to 292.5&#x2009;U/L in C5i-experienced after 7.2&#x2009;months. Three studies (n&#x2009;=&#x2009;4-63) reported reduced LDH from above the upper limit of normal levels. Six studies (n&#x2009;=&#x2009;23-70) reported reduced red blood cell transfusions (RBCt) after maximum pegcetacoplan durations of up to 12&#x2009;months, and median durations of 3.0 and 10.2&#x2009;months. Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scale scores in 1 study increased from baseline (mean 28.4) to 38.6 at 3&#x2009;months, 36.3 at 6&#x2009;months, and 34.9 at 9&#x2009;months of pegcetacoplan treatment. Two studies reported FACIT-Fatigue scores of 34.6-40.1 with pegcetacoplan for &#x2265;&#x2009;1&#x2009;month. EQ-5D mean utility scores (0.85-0.94) in 2 studies were comparable to population normative values. On the Short-Form 36 Health Survey, mental and physical component scores were slightly lower than US normative values. CONCLUSIONS: RWE indicates pegcetacoplan is associated with improved haematological outcomes, reduced RBCt dependence and fatigue, and enhanced HRQoL. These findings from real-world studies with diverse cohorts support generalizability and are broadly comparable with clinical trial evidence.

Humans

A mechanism-guided framework for prioritizing membrane-interaction anti-Vibrio peptides from peptidomics data.

A mechanism-guided framework for prioritizing membrane-interaction antimicrobial peptide candidates from proteomics-derived peptide mixtures is presented. The framework integrates conservative machine-learning-based antimicrobial peptide (AMP) screening with a literature-derived membrane-interaction plausibility (MAP) assessment and a data-driven membrane-interaction ranking function (AIPx), followed by structural visualization for interpretability. MAP encodes physicochemical characteristics commonly associated with peptide-membrane interaction and provides a graded plausibility assessment. Building upon this physicochemically interpretable framework, AIPx ranks peptides using feature weights calibrated from experimentally characterized anti-Vibrio peptides, where minimum inhibitory concentration (MIC) values are used as a coarse-grained ranking reference rather than a direct prediction target. In a peptidomics-based peptide fractionation study targeting Vibrio spp., AIPx exhibited a consistent relationship with experimentally observed antibacterial activity. Distributional analysis revealed that peptide fractions exhibiting high anti-Vibrio activity are characterized by enrichment of high-ranking peptides rather than by AMP abundance alone. By structuring AMP identification and prioritization as sequential stages, the MAP&#xa0;+&#xa0;AIPx framework enables interpretable and experimentally actionable candidate selection by reducing biologically implausible candidates. The framework facilitates species-oriented prioritization of AMP candidates, addressing a key challenge in antimicrobial peptide discovery where activity may depend on target-specific membrane characteristics. Moreover, the approach is extensible through species-specific calibration and supports interpretable, mechanism-informed prioritization in antimicrobial peptide discovery.

Proteomics

Gastrointestinal digestion governs insect protein hydrolysis and predicted bioactive peptide release: Species-dependent implications for functional food applications.

This study investigates the digestion of insect proteins and the release of predicted bioactive peptides during human gastrointestinal digestion. Using the Infogest in vitro model, mealworm, cricket, and black soldier fly larvae (BSFL) proteins were digested and analyzed through discovery proteomics and bioinformatics to identify predicted bioactive peptides. Sequential windowed acquisition of all theoretical fragment ion mass spectra (SWATH-MS) quantified insect proteins including predicted bioactive peptide precursor proteins, the precursors of predicted bioactive peptides. Results indicated that gastrointestinal digestion strongly influences peptide release, with the gastric phase exhibiting a richer predicted bioactive peptide profile than the small intestinal phase. Many predicted bioactive peptides were rapidly hydrolysed under small intestine conditions, which may lead to reduced stability or diminished activity in vivo, potentially explaining why certain peptides show strong bioactivity in vitro but limited effects in vivo. Additionally, predicted bioactive peptide release varied by insect species, influenced by genetic factors and peptide abundance. These findings highlight the importance of species selection and consideration of proteolytic digestion patterns in optimizing insect-derived bioactive peptides for functional foods and nutraceutical applications.

Animals

Discovery and characterization of multifunctional bioactive peptides from Alaska Pollock (Gadus chalcogrammus) milt: hybrid in silico, in vitro, and proteomic approaches.

The growing demand for multifunctional bioactive peptides has sparked interest in underutilized marine by-products as sustainable bioresources. This study explored Alaska Pollock (Gadus chalcogrammus) milt protein as a novel source of peptides with anti-inflammatory, anti-hypertensive, and anti-diabetic effects. Protein composition was analyzed via LC-MS, followed by in silico digestion and bioactivity prediction. Molecular docking identified peptides targeting DPP-IV, &#x3b1;-glucosidase, ACE, GLP-1 receptor, COX-2, MuRF1, and the 20S proteasome. Among the candidates, a promising peptide (CLPPH) was synthesized and validated in vitro, demonstrating inhibitory effects on nitric oxide production, DPP-IV, ACE, and &#x3b1;-glucosidase. These results highlight CLPPH's potential as a multifunctional bioactive peptide and support the valorization of Alaska Pollock milt as a sustainable source for functional foods and nutraceutical applications.

Animals

Bioactive peptides for meat quality and preservation: Integrating peptidomics and computational screening.

Bioactive peptides generated from meat proteins, fermented meat products, and slaughter by-products have attracted increasing attention as functional molecules for improving meat quality and preservation. In meat systems, peptides can be produced through endogenous postmortem proteolysis, microbial fermentation, gastrointestinal digestion, or controlled enzymatic hydrolysis of underutilized animal by-products. These peptides are closely associated with key meat science endpoints, including postmortem tenderization, oxidative stability, color retention, flavor development, microbial inhibition, and the valorization of processing by-products. However, although high-resolution peptidomics has greatly expanded the identification of meat-derived peptide sequences, their translation into practical meat applications remains limited by matrix interactions, processing stability, sensory constraints, safety concerns, and insufficient validation in real meat systems. This review synthesizes recent advances in meat-related peptidomics and computational screening, including sequence-based prediction, machine learning, molecular docking, molecular dynamics, stability assessment, and safety-oriented filtering. Particular attention is given to how these approaches can prioritize peptides with antioxidant, antimicrobial, flavor-modulating, and preservation-related functions under meat-specific technological constraints. By integrating peptide generation pathways, mass spectrometry-based identification, in silico prioritization, and meat quality endpoints, this review proposes a stage-gated framework for translating meat-derived bioactive peptides from discovery to application. Future research should strengthen matrix-specific validation, standardized peptidomic reporting, and safety assessment to support the use of bioactive peptides in meat quality improvement, clean-label preservation, and circular utilization of meat industry by-products.

Animals

Molecular mechanisms underlying umami taste perception: A DIA-based proteomic analysis of Agrocybe aegerita peptides.

The mechanisms underlying the modulation of the salivary perception of umami peptides remain poorly understood. Herein, three umami peptides (DDL, DEL, and ENG) obtained from Agrocybe aegerita were used to investigate the regulatory role of saliva in umami taste perception via a combined approach involving sensory evaluation and proteomics analysis based on 4D-DIA technology. The results revealed that umami intensity peaked at 10&#xa0;s after ingestion and was accompanied by a significant increase in saliva secretion (p&#xa0;<&#xa0;0.05). Further proteomics analysis revealed that lactotransferrin and proline-rich proteins are closely associated with the sensory perception of umami peptides. Differentially expressed proteins were mainly enriched in pathways related to saliva secretion and proteasome function. This study provides new insights from the perspectives of salivary proteomics and dynamic salivary secretion, contributing to a deeper understanding of the mechanisms by which saliva regulates umami perception.

Humans

Olive leaf protein hydrolysates yield gastro-resistant peptides with antioxidant and anti-inflammatory potential: peptidomics, in vitro validation and molecular docking analyses.

Olive (Olea europaea L.) leaves are an abundant olive-oil by-product and a promising feedstock for sustainable valorisation. An olive leaf protein isolate (OLPI) from olive-leaf powder (OLP) was enzymatically hydrolysed to yield seven hydrolysates (OLPHs). All showed notable antioxidant activity as whole hydrolysate matrices (EC&#x2085;&#x2080;&#xa0;=&#xa0;0.11-0.28&#xa0;mg&#xa0;mL-1); likely reflecting the combined contribution of released peptides and co-extracted phenolic compounds; the 15-min Alcalase product (OLPH15A) showed high activity with the shortest processing time. Its INFOGEST digest (dOLPH15A) attenuated LPS-induced inflammation in Caco-2 cells, down-regulating pro-inflammatory and up-regulating anti-inflammatory genes. Peptidomics identified 7037 peptides in OLPH15A and 534 in dOLPH15A, from which twenty gastro-resistant sequences were prioritised for in silico analysis. Multi-tool prediction and docking highlighted four peptides, GAAGGIGQPL, QSAYPGTGPL, GGGAGGGDGGIL and LDAQFPGVN, with favourable predicted affinity for the TLR4/MD2 complex, suggesting that they may contribute to the observed immunomodulatory response. These findings position olive leaves as a viable source of protein hydrolysate-based ingredients with antioxidant and anti-inflammatory potential, advancing the valorisation of olive-oil by-products.

Olea

On-filter fractionation by empFASP improves identification of membrane peptides in proteomic experiments.

Membrane proteins remain among the most analytically challenging targets in bottom-up proteomics due to their limited solubility and low abundance of protease-accessible sites within transmembrane domains. In addition, hydrophobic peptides are frequently lost during detergent removal and the on-filter processing steps. Here, we present empFASP, a straightforward on-filter-fractionation-based modification of the enhanced filter-aided sample preparation (eFASP) workflow that enhances recovery of membrane-embedded peptides otherwise lost during digestion and cleanup. The method combines controlled on-filter inversion with sequential ethyl acetate extraction at defined pH values, enabling recovery of peptide material retained on the filter and redistributed into detergent micelles. Compared with SP3 and SP4 in HEK293T lysates, empFASP increased unique hydrophobic peptide identifications by up to 48% and increased the proportion of detected transmembrane peptides. Application to mouse mitochondrial membranes and phosphatidylethanolamine-deficient and PE-containing Escherichia coli membranes showed that the additional fractions of empFASP contribute complementary recovery of hydrophobic and membrane-associated peptides, with the strongest gains observed at the peptide level. Because empFASP requires no specialized reagents or instrumentation, it can be readily implemented in standard proteomics workflows to improve coverage of membrane-embedded regions. SIGNIFICANCE: The empFASP (enhanced membrane peptide) workflow offers a practical solution to one of the persistent limitations in membrane proteomics-the underrepresentation of hydrophobic and transmembrane peptides in standard digests. By integrating simple pH-controlled extractions into an on-filter format, empFASP recovers peptides otherwise lost through adsorption or detergent micelle retention, substantially improving coverage of the membrane proteome. This method expands the analytical reach of bottom-up proteomics without requiring specialized instrumentation, making it immediately applicable for studies of membrane topology, protein-lipid interactions, and the structural consequences of altered membrane composition.

Proteomics

Detectable C-Peptide and Diabetic Ketoacidosis Risk in Type 1 Diabetes.

OBJECTIVE: To investigate whether detectable C-peptide levels in type 1 diabetes is associated with a lower risk of diabetic ketoacidosis (DKA). RESEARCH DESIGN AND METHODS: We analyzed the Diabetes Control and Complications Trial publicly available data repository for the association between detectable stimulated C-peptide (>0.2 nmol/mL, measured annually) and DKA incidence over an average 6.5-year follow-up. We used crude and adjusted Andersen-Gill models for recurrent DKA events with time-dependent covariates. RESULTS: Of the 1,441 participants (53% male, median age 27 years), 129 (9%) experienced 180 DKA events. Of these events, 179 (99.44%) occurred after C-peptide was &#x2264;0.2 nmol/L in the prior year and only 1 event occurred with C-peptide >0.2 nmol/L. C-peptide >0.2 nmol/L was associated with a DKA hazard ratio of 0.07 (95% CI 0.01-0.48; P = 0.007), consistent across adjusted models. CONCLUSIONS: Endogenous insulin production was significantly associated with lower DKA risk, suggesting that treatments preserving insulin production could decrease long-term DKA risk.

C-Peptide

Diversification of yeast proteins as an approach for the development of sustainable food systems.

Despite growing trend in sustainable protein sources, yeast proteins have mainly been explored as a source of bioactive peptides using a monospecies and general protein approach. The contribution of highly abundant protein fractions in the yeast proteome to peptide formation remains insufficiently investigated, limiting a comprehensive understanding of yeast proteins as optimized peptide sources. The current review presents a systematic analysis of yeast proteins as emerging protein sources and evaluates the suitability of high-abundance proteins as bioactive peptide precursors by in silico techniques. Moreover, brewery by-product and single-cell yeast protein approaches are compared in terms of composition and techno-functionality whereas peptide formation mechanisms (in situ and ex situ) and regulatory aspects for food applications are also addressed. Cytoplasmic metabolic proteins, particularly glycolytic enzymes (GAPDH), are identified as highly abundant fractions of the yeast proteome. Proteins associated with cell and organelle membranes also contribute substantially based on cellular localization. These findings imply that such proteins may act as key precursors of yeast-derived bioactive peptides. In silico hydrolysis with Alcalase suggests a tendency toward the generation of short-chain peptides (3-11/14 aa), which may support biological activity. Moreover, peptide profiles appear to vary across yeast species, highlighting the role of species diversity in peptide generation. While single-cell yeast protein allows more controlled production than brewery by-products, nucleic acid content in both may limit applications. Overall, yeast proteins appear to be metabolically adaptable and species-diverse sources for various biological peptides.

Saccharomyces cerevisiae